Fix clone_partitions not performing cloning in online upgrade

Fix clone_partitions not performing cloning in online upgrade

In order for the upgrade state to be completed, upgrade_progress_status
must be equal to 100. Previously this value was set by the
online-update-success service, but this service is executed after the
upgrade-manager service. As a result, the upgrade state is never
switched from "ready" to "completed" preventing clone_partitions from
taking its job.

The solution is to take over the responsibility for setting the upgrade
progress status by the update.sh script instead of the
online-update-success.sh (which is executed from online-update-success
service). This way handling of the progress becomes unified regardless
of the upgrade type.

Change-Id: I1d599251986dac7a378a44545e8dcce285ccab89